Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
A wireless communication network may include a number of base stations that can support communication for a number of user equipments (UEs). A UE may communicate with a base station via the downlink and uplink. The downlink (or forward link) refers to the communication link from the base station to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the base station.
A UE may be configured to re-send an uplink transmission until it receives a positive acknowledgement (ACK) that the uplink transmission was successfully received by a base station. In some cases, even after a UE has received an ACK, it may still be expected to keep decoding a control channel (e.g., a PHICH or PDCCH). This is because even if the base station did not successfully receive the UL transmission, it may use an ACK to suspend the retransmission, for example, to grant resources for transmissions that may be higher priority at that instant. Without continued decoding of the control channel, a subsequent grant for re-transmission would not be detected so there would be no re-transmission, which would result in a packet drop. In addition, this approach allows eventual retransmission in the event a negative acknowledgement (NACK) was transmitted, but somehow interpreted as an ACK.
Unfortunately, continued decoding of an acknowledgement channel may limit the amount of time a UE stays in a low power state, which may lead to unnecessary power consumption.